White Harlequin Flower Sparaxis bulbifera (L.) Ker Gawl.
Synonyms - Sparaxis grandiflora, Ixia bulbifera
Family: - Iridaceae
Names:
Sparaxis is from the Greek sparasso meaning I tear and refers to the torn tips of the spathe "leaf" under the flower.
Bulbifera refers to the bulbils or cormels produced in the leaf axils.
Harlequins were Italian pantomime comics that dressed in multicoloured costumes and refers to closely related species that have multicoloured flowers.
Other Names:
Harlequin Flower
Sparaxis
Summary:
White Harlequin Flower is a small tufted herbs with a fan of leaves arising annually from a corm. Flower spikes to 0.5 metres high with several 6-petalled, white to pale yellow flowers with a yellow centre. It has 3 white anthers and a 3-branched style. Cormels are produced in the leaf axils after flowering.
Native to South Africa and were introduced as garden plants and are now weeds of roadsides, particularly near old settlements. They flower in spring and hybridise easily.
Description:
Cotyledons:
One.
First leaves:
Leaves:
5-10 emerging from the base of the plant and of similar length. Waxy and non wetting.
Stipules - None
Petiole - None
Blade - 50-300 mm long by 3-12 mm wide. Soft texture. Parallel sided to sword shaped tapering gradually to a pointed tip. Mid veins are prominent. Edges smooth, base clasping. Green on both sides. Hairless
Stem leaves - 1-2
Stems:
Flower stem - 100-600 mm tall by 2-4 mm diameter, usually a few (1-3) branches but may be single. Firm, wiry, erect, smooth and hairless
Flower head:
1-6 flowers on a zig-zag stem in a spike. Bracts under the flower 10-25 mm long, membranous, whitish with brown lengthwise veins and usually torn for much of their length often with 1-4 rigid cusps usually with red-brown tips.
Flowers:
20-30 mm long by 10-20 mm diameter, 6-petalled, white to pale yellow, funnel shaped flowers with purple tinges or stripe and a yellow centre.
Ovary - Inferior, Many ovules.
Style - Thread like, white, 3 curved branches, 6-10 mm long. Arched to lie behind the stamens and protruding above the anthers
Perianth - Tube yellow or green, cylindrical at the base and funnel shaped near the top, 12-16 mm long and shorter than the petals.
"Petals" (Lobes) - 6, white to pale yellow, 20-30 mm long by 7-12 mm wide, sword shaped. Outer ones may be purple streaked. Sometimes the whole flower or some petals may be purple or have purplish blotches.
Stamens - 3. Asymmetrically arranged around the style.
Filaments - free.
Anthers - 3, white, 5 mm long, slightly curved at the tip and attached at the base
Fruit:
Oblong, leathery, membranous, light green capsule, 10 mm long, wrinkled crosswise and flat on top.
Seeds and reproductive propagules:
Seeds, many, 2 mm diameter, globular, smooth, black or reddish black. Appear to be produced in WA and NZ only.
White, globular underground corm, 9-16 mm diameter covered with a grey brown, soft, fibrous, closely woven covering (tunic).
1 to many, 5 mm long cormels (bulbils) are produced in leaf axils after flowering.
Roots:
Corm with short, fine, fibrous roots.
Key Characters:
3 stamens
1 sessile flower in each spathe.
2 floral bracts. Outer floral bract divided almost to the middle.
Style branches simple or minutely 2 lobed.
Perianth white to cream or pale yellow coloured inside and usually purplish outside. Sometimes purplish inside or with a dark spot in the middle but lacking a dark blotch immediately above the yellow throat or sometimes with a yellow marking on the lower lobes.
Stamens with anthers grouped on one side of the style.
Anthers white.
Spathe bracts deeply lacerate with spreading subulate tips.
Several cormels (bulbils) in most leaf axils.
Adapted from J. Black, T.A. James, E.A. Brown, G. Perry
Biology:
Life cycle:
Corms sprout in autumn and produce leaves over winter. The flowering stem is produced in spring and it flowers soon after. Large numbers of cormels are formed in leaf axils after flowering. The top growth dies off with the onset of summer and the plant survives on its corm.
Physiology:
Reproduction:
Seeds, corms and cormels.
Flowering times:
September to October in WA.
September to November in SE Australia.
September to November in NSW.
Seed Biology and Germination:
Vegetative Propagules:
Underground corm and numerous cormels in leaf axils.
Hybrids:
Hybridise easily.
Allelopathy:
Population Dynamics and Dispersal:
Spread by slashing, mowing, wind, water, dumped garden refuse, earthmoving, road making and graders and intentional planting.
Weeds of roadsides, particularly near old settlements, bushland, drainage lines, seasonal wetlands.
Invasive and competitive weed of bushland often forming monocultures on disturbed areas.
Poor palatability and rarely eaten by stock.
Toxicity:
Symptoms:
Treatment:
Legislation:
Management and Control:
Regular mowing provides control if it is done regularly before flowering. Mowing after flowering will spread cormels and increase the spread of the infestation.
Light grazing often makes the infestation worse.
Always use a wetting agent when spraying as the foliage is water repellent.
Roadsides can be overall sprayed with 10 kg/ha 2,2-DPA plus 0.25% wetting agent with minimal damage to most established native plants.
Thresholds:
Not usually a weed of crops and pastures.
Eradication strategies:
These plants are very difficult to control by hand weeding because they produce seed, cormels in the leaf axils and underground corms. Loosen the soil before removal to prevent the corm breaking off. Conduct weeding before flowering and cormel formation.
Spray during August or September before the end of flowering with 100 mL glyphosate(450g/L) plus 25 mL Pulse Penetrant® in 10 litres of water
OR 0.1 g metsulfuron(600g/kg) plus 25 mL Pulse Penetrant® in 10 litres of water
OR 1000 g 2,2-DPA plus 25 mL Pulse Penetrant® in 10 litres of water . The area will require spraying again next season to control the tiny seedlings and plants emerging from cormels. Good control can usually be achieved in 2-3 years.
Painting leaves or wiping with a sponge glove dipped in a mixture of 1 part glyphosate(450g/L) in 2 parts water can be used in sensitive areas.
Replant native shrub species if necessary.
Avoid road works that carry new corms or cormels into the area.
Start control at the top of the catchment to stop seed and cormels transported in water reinfesting treated areas.
Herbicide resistance:
None reported.
Biological Control:
Related plants:
Sparaxis pillansii = Sparaxis tricolor
Sparaxis pillansii has purple-pink flowers with a dark maroon to purple band and a yellow centre and 3 yellow to brown anthers whereas Sparaxis bulbifera has white flowers and 3 white anthers.
Plants of similar appearance:
Dierama
Freesia
Ixia
Synnotia
Tritonia
References:
Black, J.M. (1965). Flora of South Australia. (Government Printer, Adelaide, South Australia). Part 1, P381.
Bodkin, F. (1986). Encyclopaedia Botanica. (Angus and Robertson, Australia).
Blood, K. (2001). Environmental weeds: a field guide for SE Australia. (CH Jerram & Associates, Australia). P162-163. Photo.
Everist, S.L. (1974). Poisonous Plants of Australia. (Angus and Robertson, Sydney).
Harden, Gwen J. (1991). Flora of NSW. (Royal Botanic Gardens, Sydney). Volume 4. P128. Diagram.
Hussey, B.M.J., Keighery, G.J., Cousens, R.D., Dodd, J. and Lloyd, S.G. (1997). Western Weeds. A guide to the weeds of Western Australia. (Plant Protection Society of Western Australia, Perth, Western Australia). P36. Photo.
Lazarides, M. and Cowley, K. and Hohnen, P. (1997). CSIRO handbook of Australian Weeds. (CSIRO, Melbourne). #943.1.
Marchant et al (1987). Flora of the Perth Region. (Western Australian Herbarium, Department of Agriculture, Western Australia). P803.
Moore, J.H. and Wheeler, J.R. (2002). Southern Weeds and their Control. P110-111. Photos.
Muyt, A. (2001). Bush Invaders of South-East Australia: a guide to the identification and control of environmental weeds found in South East Australia. (R.G and F.J. Richardson, Australia). P97-98. Photos.
Paczkowska, G. and Chapman, A. (2000). The Western Australia flora: a descriptive catalogue. (Wildflower Society of Western Australia (Inc), the Western Australian Herbarium, CALM and the Botanic Gardens & Parks Authority). P72.
Randall, J.M. and Marinelli, J. (1996) Invasive Plants. (Brooklyn Botanic Gardens Inc. Brooklyn). P. Photo.
Wheeler, Judy, Marchant, Neville and Lewington, Margaret. (2002). Flora of the South West: Bunbury - Augusta - Denmark. (Western Australian Herbarium, Bentley, Western Australia). P328. Diagram.
Acknowledgments:
Collated by HerbiGuide. Phone 08 98444064 or www.herbiguide.com.au for more information.